Radio-receiving and scanning system



Dec. 9, 1958 R. H. RINES 2,864,030

RADIO-RECEIVING AND SCANNING SYSTEM Original Filed March 18, 1944 2 Sheets-Sheet 1 Dec. 9, 1958 R. H. RINES 2,864,030

RADIO-RECEIVING AND SCANNING SYSTEM Original Filed March 18, 1944 2 Sheets-Sheet 2 Hike - f Genera or z 1/1, j 211 uni. II IIII 1' Amplifier RADIO-RECEIVING AND SCANNING SYSTEM Robert Harvey Rines, Brooldine, Mass.

Original application March 18, 1944, Serial No. 527,375. Divided and this application May 23, 1947, Serial No. 750,022

35 Claims. (Cl. 315-1) The present invention relates to electric systems, and more particularly to radio-receiving systems that, whlle having more general fields of usefulness, are especially adapted for use in television. The present application is a division of application, Serial Number 527,375, filed March 18, 1944.

An object of the invention is to provide a new and 1mproved radio-receiving system embodying a novel cathoderay-tube member having a novel radio-receiving mosalc.

Another object is to provide a new and improved television system.

Another object of the present invention is to provide a new and improved radio-locator system for both detecting the presence of a body and rendering it visible.

Other and further objects will be explained hereinafter and will be more particularly pointed out in the appended claims.

The invention will now be more fully explained in connection with the accompanying drawings, in which Fig. 1 is a diagrammatic view of circuits and apparatus arranged and constructed in accordance with a preferred embodiment thereof; Fig. 2 is a view of a modification; Fig. 3 is a diagram showing an airplane object from which radio waves are reflected and scattered to the receiving system of Fig. 1; and Fig. 4 is a view of a further modification.

An electromagnetic-wave generator 4 is shown exciting dipole 2 to produce ultra high-frequency pulsed-rad1o energy, say, of 3 or 1.5 centimeters wave-lengths. A continuous-wave or any other type of modulated-wave generator may be employed, but pulsed energy, at present, has the advantage of economical and easy high-power ultra-high-frequency generation.

I The waves emitted by the dipole 2 may be directed by a reflector 3 upon a parabolic reflector 6. The parabolic reflector 6 is shown directing the waves toward an object, say, an airplane 8, from which they are reflected and scattered toward a receiving station.

At the receiving station, the radio waves thus reflected and scattered from the object 8 may be focused by an electromagnetic dielectric lens 5, such as polystyrene, upon a bank or array 7 comprising a plurality of radioreceiving pick-up unit antenna elements. The dielectric lens may be replaced by any other type of well-known lens, mirror or other directive system for focusing the electromagnetic energy scattered and reflected from the object 8 on the bank or array 7 of pick-up elements.

The pick-up elements of the bank or' array 7 are shown arranged in two dimensions in the form of rows and columns, in the proximity of the focal plane of the lens 5. The first or uppermost row of the bank is illustrated as comprising the sections 10, 12, 14, 16, etc., shown as equally spaced horizontally. The second row from the top is shown comprising the sections 18, 2'0, 22, etc. The third or next-lower row is shown comprising the sections 24, 26, etc., and so on for the remaining rows of pick-up elements. Though only a small number of pick-up units is shown in each row, this is merely for illustrative purposes, in order not to confuse the disclosure. It will be understood that, in practice, a large number of pick-up units will be employed in each row, say, 180.

The sections 10, 18, 24, etc., are arranged in the first or right-hand column. The sections 12, 20, 26, etc., are disposed in the second column from the right. The sections 14, 22, etc., are disposed in the third column from the right, and so on. There may be as many columns as there are pick-up units in each row. Though each column is shown as comprising only a few pick-up units, this is again in order not to complicate the drawings.

The pick-up units will, of course, all receive the reflected or scattered radio waves through the lens 5 simultaneously. There will be focused on each pick-up unit radio-frequency energy of a voltage corresponding to the scattering from a corresponding view of the object 8. The pick-up elements will thus receive different field strengths of radio energy, corresponding to the amount of energy reflected or scattered from the variou parts of the object 8 and converged upon the array 7 of pickup elements by the lens 5. A radio-energy picture of the object 8, as will presently he explained, is thus recorded upon the array, specific elemental areas of which will correspond to specific elemental areas of the object 8. By means of the present invention, this radio-energy picture may be converted into a visible picture 123. According to the preferred embodiment of the invention, the visible picture 123 is caused to appear upon the fluorescent viewing screen 106 of a display cathode-ray oscilloscope tube 90. Though the tube 90, and also the hereinafter described cathode-ray oscilloscope-like member 89, are shown operating on the electrostatic principle, magnetic deflection or a combination of magnetic and electrostatic forces may be employed. The invention provides a means for producing upon the screen 1&6 images corresponding to the radio frequency energy received by the pick-up elements.

Provision is made for first rendering the normally ineffective pick-up units 10, 12, 14, 16, etc., of the first row successively effective momentarily in the display circuits; for then rendering the pick-up units 18, 20, 22, etc., of the second row successively effective momentarily; for then rendering the pick-up units 24, 26, etc., of the third row successively effective momentarily; and so on, the pick-up units thus being rendered effective in two-dimensional order.

The pick-up units are shown arranged in an insulating disc, bank or array 9, at the screen end of the oscilloscope-like member 89, and the pick-up units may be constituted of small crystal beads of uranium oxide insulatingly set into the support disc 9. Any similar mosaic of radio-wave absorbing and rectifying crystals such as silicon, for example, may be employed. The beads 10, 12, 14, 16, etc. of the first row are all connected to a grounded strip 43. The beads 18, 20, 22, etc., of the second row are similarly shown all connected to another grounded strip 51. The beads 24, 26, etc., of the third row are similarly shown all connected to a third grounded strip 57, and so on.

' The cathode-ray-oscilloscope-like member 89 is shown provided with a cathode 95, a control-grid electrode 93 and an anode 97. Electrons emitted from the cathode 95 will become enabled, in response to proper stimulation of the grid 93, to pass by the grid 93 to the anode 97 of the member 89. The electrons will continue to travel in a stream from the anode 97 between a pair of vertically disposed deflector plates 99 and 101, of which the plate 99 is shown grounded, and between a pair of horizontally disposed deflector plates 103 and 105, of which the plate 105 is shown grounded, to impinge finally on the disc 9 of the member 89. A horizontal-sweepr 3 time base, applied, as hereinafter more fully explained, to the vertically 'disp'os'ed deflector plates99 and '101, will cause the electron stream from the cathode 95 to become deflected horizontally, and a vertical-sweep-time base, applied to 'the horizontally dispos'ed 'cl eflectorplat'es 103 and' 105, will cause the electron stream to become deflected vertically. The rows of pick-up u'nits niay be positioned along the successive paths of the electron stream so that the stream can impinge on them as the electron stream successively sweeps out the successive rows of the array 7. The front surface of each crystal pick-up element is exposed in the direction of the incoming radio waves, and the rear surface of each element is exposed. within the cathode-ray-tube memberj89 to the electron stream.

If, accordingly, the lens Sis caused to focus the radioen er'gy picture on the oscilloscope-likemember $9, the bank of uranium-oxide globules will act to absorb the incident energy. Silicon and uranium oxide detectors and similar crystals areknown to absorb radio-frenquency energy, and to exhibitnegative temperature coeflicients of resistance. Because of its high temperature coefficient of resistance, the resistance of the uranium oxide will change with the intensity of the impinging radiofrequency energy.

The radio-frequency energy will become rectified to produce direct-current potential differences across the resistance of the uranium oxide. This results from the detecting properties of the uranium oxide in the radioreceiving circuits traceable from the crystal electrodes through the crystals to the grounded conductor 78. These potential differences are respresentative of the radiofrequency energy impressed on the uranium oxide in the radio-receiving circuits comprising the uranium oxide units and the ground conductor 78. The variations of resistance and potential along the bank of globule beads are thus a measure of the radio-frequency energy impinged on the array by the lens'5. The resistance of the uranium oxide, since its temperature coeflicient is negative, changes with the intensity of'the impinging radiofrequency energy. The resistance variation thus also produced along the bank of uranium-oxidebeads is representative of the radio-frequency energy received by' the respective beads. 7

A radio-energy image of the object 8'becomes thus recorded upon thearray of uranium-oxide'beads.

The bank of uranium-oxide globules maybe scanned according to either of two principles or according to a combination of the same. One principleirivolves measuring the variation in the resistance of the-bank at the moment that the electronstream impinges upon "the" successively disposed'beads to 'short-circuit'them. This pro vides. a measure of theresist-ance' across the uraniumoxide beads, indicative "of the radio-frequency energy impinged on the particularibead upon whichtheelectron stream has impinged. The otherprinc'iple' involve's measuring in the amplifier '79 the current along the electron stream as it impinges upon areas of different potential of the variably resistive beads, completing the circuit to the. ground through the successive crystals by way of the conductor 78.

Each uranium-oxide bead will absorb and rectify the radio-frequency energy. Dependent upon the magnitude of this energy, it will changethe resistance of the uranium oxide. This change will re'sult as a consequence of the. absorption and the're'ctifyi ng action by' the uranium oxide of'the radio-frequency energyreceived' by it. Asthe (electron stream" successivelyimpinges upon the successively disposeduranium-oxide"beads, during the scanning, 'it'successively measures the resistance of' the successive crystals. This produces a corresponding change in the input voltage to a grounded preferably linear amplifier 79, indicative of the radio-frequency energy impinged on the respective uranium-oxide beads.

The scanning of these crystals may obviously also 54 i V operate on the principle :of change in electron:beam current upon" impinging on surfaces of various potentials.

As the stream hits these crystals of different potentials,

a change in beam current occurs, which manifests itself in the input circuit of the amplifier 79.

Mosaics of silicon, as shown in Fig. 1, or alternate sections of silicon and metal; as shown in Fig. 4, or dielectric and silicon, maybe mounted in the disc 9 of the escino'scope'ss and may similarly be' used "as a scanning mosaic. Radio-frequency energy impinged on the metal sections 200, 202, etc., will produce rectified voltages across the adjacentlyadispo'sed:silicon sections 201, 203, etc," in the radio-receiving circuits itrac'e'able from the metal sections through the adjacentlydisposed silicon sections by 'way of 'the common lead 78. The rectifying sections of silicon may follow the square law in their response, but this can be compensated for by proper design of the amplifier 79 (page 492 of Ultra High Frequency ',Techniques,f "Braine'rd, Koehler, Reich and woeamngigaz edition).

The exposed silicon"'sectio'ns' will also absorb"radio energy and'exhibit a negative-resistance effect. The electron scanning of the successive 'siliconsections'will thus operate, as before described, to measure theresist'ance variation of the sections, orthecha'ngein beam current upon impinging on sections of different potential, or according to a combination of the two' principles.

As the electron stream produced from the cathode 95, in response to appropriate horizontal swep-tim'e-base voltages applied tothe vertically disposed'deflector plates 99 and 101 of the cathode-ray tube-like member 89, travels across the pick-up elements in the disc 9, it will successively discharge into the amplifier 79, by way of a conductor 78. If desiredjthe amplifier '79 may be replaced by a bank of linear amplifiers, onecorresponding to each of the pick-up elements. p

The output of the amplifier 79 will obviously vary, at successive instants, in accordance with the radio-frequency energy received by the successive-corresponding pick-up elements. v g p a V v A pulse generator 40 may be employed to trigger a horizontal-time-base-sweep "circuit '63 "and a verticalsweep circuit 69, according to conventional and well- :known television technique. The pulse generator 40 may feed, through an attenuator 'andrectifier 1, to an oscillator or any similar or equivalent television circuit. One such circuit is shown as a pulse-recurrence-freqhency multiplier 65, for applying many pulsescorresponding to each radio-frequency pulse forthe-period' between successive radio'pulses, to trigger the horizontal-sweep circuit 63. The horizontal-time-base sweep will thereby be produced between the vertically disposed'deflector plates 99 'and 101, occurringas'many times, say, between successive radio-frequency transmissions, as there are rows of pick-up antennas. The pulse generator 40 may also feed, through the attenuator and rectifier 1, to trigger the vertical-sweep circuit 69, once corresponding to every radio-frequency transmission. 'One vertical sweep will then occur between the horizontally'disposed plates 103, 105 during the period between successive radio-pulse transmissions, corresponding'to as many horizontal sweeps as there are rows of antennas, causing each of the horizontal sweeps to appear at'successively lower levels on the oscilloscope-sweep face.

If the circuit- 65 comprises anoscillator, the oscillations may be employed to trigger the horizontalsweep. The period of the oscillations which, as *previously explained, is much less than the duration of each radiopulse, corresponds to the time ofsweep across'one'row of the pick-upunits in the disc 9. If, as previously men- -tioned, continuous-wave radio transmission is employed,

the vertical 'sweep circuit 69'may'be triggered to produce :one vertical sweep corresponding to as'rnany horizontal sweeps from the horizontal-sweep circuit 63'a's there are rows of receiving units.

Means is provided for producing upon the screen 106 of the display oscilloscope 90, images corresponding to the radio-frequency energy received by the corresponding pick-up mosaic antenna elements. The screen 106 is illuminated by an electron stream in the oscilloscope 90. This electron stream is synchronized to travel with the electron stream of the cathode-ray-like member 89. The horizontal-sweep circuit 63 is connected to the horizontal-deflector plate 100 of the oscilloscope 90 by a conductor 67, and to the horizontal-deflector plate 101 of the oscilloscope-like member 80 by the conductor 67 and a conductor 124. The vertical-sweep circuit 69 is connected to the vertical-deflector plate 102 of the oscilloscope 90 by a conductor 71, and to the vertical-deflector plate 103 of the oscilloscope-like member 89 by the conductor 71 and a conductor 146.

The amplifier 79 is connected, by conductors 84 and 86,

connected, by conductors 85 and 87, to the control-grid electrode 92 and the cathode 94. of the oscilloscope 90. The mosaic beads become thus successively connected, through the amplifier 79 and the phase-inverter 81, to the control electrode 92. Electrons emitted from the cathode 94 will become enabled, in response to the action of the amplifier 7'9 and the phase-inverter 81, to pass by the grid 92, to the anode 96 of the oscilloscope tube 90. The electrons will continue to travel in a stream from the anode 96, between the pair of vertically disposed oscilloscope deflector plates 93 and 100, of which the plate 98 is shown grounded, and between the pair of horizontally disposed oscilloscope deflector plates 102 and 104, of which the plate 104 is shown grounded, to impinge finally on the fluorescent viewing screen 106 of the oscilloscope 90. The horizontal-sweep-time base applied to the vertically disposed deflector plates 98 and 100 will cause the electron stream from the cathode 94 to become deflected horizontally, and the vertical-sweep-time base, applied to the horizontally disposed deflector plates 102 and 104, will cause the electron stream to become deflected vertically, in synchronism with the horizontal and vertical sweeps scanning the mosaic 7 of the oscilloscope-like member 89.

After each simultaneous horizontal sweep of both the oscilloscope 90 and the oscilloscope-like member 89 has been completed, a successively larger voltage will be applied to the horizontally disposed deflector plates 103, 105 and 102, 104, respectively, by the vertical sweep circuit. After the last such horizontal sweep, the voltage between the horizontally disposed plates 103, 105 and 102, 104 will become restored to zero. The next horizontal sweep, therefore, will start again at the first or top row.

successively disposed areas of the screen 106 of the oscilloscope 90 will therefore correspond to the similarly disposed mosaic-antenna sections in the disc 9 of the member 39. Each spot along a particular horizontal sweep, therefore, will become brightened on the screen 106 according to the amount of radio energy received by the corresponding pick-up elements, and fed, by way of the amplifier 79 and the phase-inverting-and-amplifying circuit 81, to the control electrode 92 of the cathode-ray oscilloscope 90.

A more sensitive video signal device might be any wellknown resistance-measuring circuit, such as a bridge detector of, say, the Wheatstone construction. If the uranium-oxide or other crystal globules have their resistances connected in a direct-current series circuit, then the bank of crystals may serve as an extremely sensitive radiodetecting element of a Wheatstone bridge, in which they may be balanced against fixed elements 212, 21d and 216, as shown in Fig. 2. The short-circuiting of each successive globule or resistance by the electron stream, diagrammatically shown as short-circuiting switches 205, 207, 209, 211, in parallel with the globules 2-04, 206, 208, 210, Would thus be markedly indicated in the amplifier 79 and fed to the control electrode 92 of the display oscilloscope 90.

Although the invention has been described in connec tion with mosaic-antennas arranged in rows and columns, it will be understood that this is not essential, for other arrangements are also possible. Antennas arranged along concentric circles covering the field, or a continuous spiral, will also serve, though the oscilloscope arrangement would, of course, be correspondingly modified, as is Wellknown in the art, to render successive circles of the receiving units successively effective, in two-dimensional order.

Further modifications will occur to persons skilled in the art, and all such are considered to fall within the spirit and scope of the invention, as defined in the appended claims.

What is claimed is:

1. An electric system having, in combination, an oscilloscope-like member having a mosaic of radio-receiving eiements for absorbing radio waves and means for producing an electron stream for impinging directly upon the elements, and means for causing said stream to scan the elements.

2. An electric system having, in combination, an oscilloscope-like member having a mosaic of absorbing-andrectifying radio-receiving elements and means for producing an electron stream for impinging on the elements, and means for causing said stream to scan the elements.

3. An electric system, having, in combination, an oscilloscope-like member having a mosaic of uranium-oxide 'absorbing-and-rectifying radio-receiving elements and means for producing an electron stream for impinging on the mosaic, and means for causing said stream to scan the mosaic.

4. An electric system having, in combination, an oscilloscope-like member having a mosaic of silicon absorbingand-rectifying radio-receiving elements and means for producing an electron stream for impinging on the mosaic, and means for causing said stream to scan the mosaic.

5. An electric system having, in combination, an oscilloscope-like member having a mosaic of alternately disposed silicon and metal radio-receiving elements and means for producing an electron stream for impinging on the mosaic, and means for causing said stream to scan the mosaic.

6. An electric system having, in combination, radioreceiving means, means for producing an electron stream for impinging directly upon the radio-receiving means, and means for causing the electron stream to scan the radio-receiving means.

7. An electric system having, in combination, radioreceiving-and-rectifying means, means for producing an electron stream for impinging on the radio-receiving-and rectifying means, and means for causing the electron stream to scan the radio-receivingand-rectifying means.

8. An electric system having, in combination, a plurality of radio-rectifying elements exhibiting negative temperature coeflicients of resistance when exposed to radio waves, and means for producing an electron stream impinging on the elements.

9. An electric system having, in combination, an oscilloscope-like member having a mosaic of radio-receiving elements disposed in two dimensions and means for producing an electron stream for impinging directly upon the mosaic, and means for causing said stream successively to scan the elements in two-dimensional order.

10. An electric system having, in combination, an oscilloscope-like member having a mosaic of normally ineffective radio-receiving elements, means for producing an electron stream impinging directly upon the elements, and means for causing said stream to scan the elements successively to render them eflective.

11. A cathode-ray-tube oscilloscope having a screen provided with a plurality of radio-receiving elements and means for producing an electron stream for impinging upon the screen, the front surfaces of the elements being exposed in the direction of the incoming radio waves and the rear surfaces of'the elements being exposed Within the cathodcqay-tube' to the'electron stream.

l2. An electric system having, in combination, an oscilloscope-like member having a mosaic of radio-wave absorbing-and-rectifying -crysta'ls, means for producing an electron stream for impinging on'the crystals, and means for causing said stream'to scan the crystals.

13. An electric system having, in combination, an oscilloscope-like member having an insulation'support and plurality of absorbing-and-rectifying' radiou-ecei'ving elements carried by the support, means for producing an electron stream forimpinging on the "elements, and means for causing said stream to scan the elements.

14. An electric system having, in combination, a plurality of sets of radio-rectifying elements exhibiting negative temperature coefficients of resistance when ''exposed to radio Waves, the elements of each set being connected togetherto' a common-terminal, a load, means for connecting the common terminals to the load, and means for producing an electron stream impinging on the "elements.

15. An electric system having, in combination, an oscilloscope-like member having a mosaic of-radio-Wave absorbing andd'ectifying crystals disposed in two dimensions, means for producing an electron stream for impingingon the mosaic, and means for causing said stream successively to scan the crystals in two-dimensional order.

16. An electric system having, in combination, an oscilloscope-like member having a mosaic of normally ineffective radio-wave absorbing-and-rectifying crystals, means for producing an electron stream impinging on the crystals, and means for causing said stream to scan the crystals successively to render them effective.

17. A cathode-ray-tube oscilloscope having means for producing an electron stream and a screen provided With a plurality of radio-Wave absorbing-and-rectifying crystals, the front surfaces of the crystals being exposed in the direction of the incoming radio Waves and the rear surfaces of the crystals being exposed within the cathoderay-tube to the electron stream, and means for directing the electron stream upon the rear surfaces of the crystals.

18. A mosaic having an insulating support, aplurality of radio-receiving-and-rectifying elements insulatingly'set into the support in order independently to receive and rectify radio Waves, and means for impinging an electron stream upon the mosaic.

19. A. mosaic of'mutually insulatedradio-receiving antenna elements eachprovided Withmeans capable of absorbing and rectifying the radio Waves received thereby, and means for impinging an electron stream upon the mosaic.

20. A mosaic-havinganinsulating support, a plurality of antennas for independently receiving radio Waves 'insulatinglyset into the support, and means for impinging an electron stream upon the mosaic.

21. An electric system having, in combination, a mosaic comprising a plurality of antenna elements 'for receiving radio waves each provided with a radio-wave absorbing and rectifying element having a negative temperature coefficient of'resistance, the-resistance'of each absorbing and rectifying element varyingin accordance With the radio Waves received 'bythe-corresponding antenna element, means for focusing a distribution of radio waves upon the mosaic in order to -produce a corresponding resistance distribution upon the absorbing and rectifying elements, and means for scanning the mosaic.

22. An electric system having, in combination, a mosaic comprising a plurality of antenna elements'for receiving radio Waves each provided with a rectifying element for producing a rectified voltage in response to the radio Wavesreceived. by the corresponding element,

means for focusing a distribution of radiowaves upon the mosaic in order to produce acorresponding rectifiedvoltage distribution upon the rectifying elements and means' -for scanning :the' rectified-voltage distribution.

it 23. An electric system having, in combination, a mosaic comprising a plurality of antennwelements' for eceiving 'iradio Waves e'ach' provided with. a rectifying element for-producing a' rectified voltagei in response "to the radio waves "received by the corresponding. element, means forf focus'ing adistribution of radio Waves. upon the mosaicin-order to'producea corresponding rectifiedvoltage distribution upon-"the I-rectifying "elements and electron stream means for scanning the rectified-voltage upon the successive rectifying elements.

24. 'Anelectric system having, in combination, a mosaic icomprising a plurality of. antenna elements: for receivingi'radiowaxes leach'. provided with a rectifying element for producing a rectified voltage 'in'response'to the radio Waves. received *by: the corresponding :element, means for ,preventing'interference between -adjacent antenna elements, and means for impinging. ancelectron streamLup'onrthesrnosaic.

.25.: A. mosaic.-having.:an insulating support and'an antennaarray comprising aplurality of closely spaced conductors of dimensions appropriate to receiveradio W21VS"0f a predetermined frequencyv insulatingly supported "by the support in order independently to receive "the radio Waves, each conductor. being. provided with a rectifying element for rectifying the radio Wavesreceived by the corresponding antenna conductor, and'means for scanning the mosaic. V

26:An electric system? having,iin combination, a mosaic provided With an antenna array. comprising a plurality of closely :spaced conductors of dimensions appropriate to'receive' radio Waves of a predetermined frequency, each conductor being provided with a crystal detector for rectifying the radio waves received by the corresponding antenna conductor; a load connected to the conductors, and means for scanning the antenna array to cause successive indications in the load representative of the radiowaves received by the successive antenna conductors and rectified by their corresponding crystal detectors.

27. An electric system having, in combination, a

-m0saic provided With-an antenna array comprising a plurality of closely spaced conductors of dimensions the rectifying -eletne'nts in the form of a mosaic, each rectifying-element being poled with its conductive di- 'rection the same as the other elements in ordervv that radio --waves received by the elements maygive rise to alte nating currents that are rectified at the rectifying boundaries to produce corresponding electric charges thereon,

and electron-stream means for scanning the elements.

29. A plurality of spaced rectifyingelements each having a conductor dividedinto two portions separated by a rectifying boundary region, means for supportingthe rectifying elements in the formof amosaic, each recti fying elementbeing poled with its conductive direction -thesame as the other elements in order that radio waves received by the elements may give rise to alternating currents that are rectified at the rectifying boundaries to pro- 7 duce corresponding electric charges thereonand means for periodically discharging the rectifying elements in succession, thereby to produce a fluctuating current varying in accordance With the radio Waves received by and thecorresponding charges produced on the successive elements.

30. An electric system having, in combination, an oscilloscope-like member having a mosaic of dipole antenna radio-receiving elements and means for producing an electron stream for impinging on the elements, and means for causing said stream to scan the elements.

31. An electric system having, in combination, an oscilloscope-like member having means for producing an electron stream, a mosaic of radio-receiving elements each provided with and connected to a corresponding electric circuit comprising a radio-wave absorbing-andrectifying element, means for impinging the electron stream on predetermined portions of the radio-receivingelement electric circuits, and means for causing the electron stream to scan the said predetermined portions of the radio-receiving-element electric circuits.

32. An electric system having, in combination, a mosaic comprising a plurality of antenna elements for receiving radio waves each provided with a radio-wave absorbing and rectifying element having a negative temperature coefiicient of resistance, the resistance of each absorbing and rectifying element varying in accordance with the radio waves received by the corresponding antenna element, means for focusing a distribution of radio waves upon the mosaic in order to produce a corresponding resistance distribution upon the absorbing and rectifying elements and means for measuring the resistance distri bution so produced.

33. An electric system having, in combination, a mosaic comprising a plurality of antenna elements for receiving radio waves each provided with a radio-wave absorbing and rectifying element having a negative temperature coefiicient of resistance, the resistance of each absorbing and rectifying element varying in accordance with the radio waves received by the corresponding antenna element, means for focusing a distribution of radio waves upon the mosaic in order to produce a corresponding resistance distribution upon the absorbing and rectifying elements and means for measuring the resistance of the successive absorbing and rectifying elements.

34. An electric system having, in combination, a mosaic comprising a plurality of antenna elements for receiving radio waves each provided with a rectifying element for producing a rectified voltage in response to the radio waves received by the corresponding element, means for focusing a distribution of radio waves upon the mosaic in order to produce a corresponding rectified-voltage distribution upon the rectifying elements and means for measuring the rectifiedwoltage distribution.

35. An electric system having, in combination, a mosaic comprising a plurality of antenna elements for receiving radio waves each provided with a rectifying element for producing a rectified voltage in response to the radio waves received by the corresponding element, means for focusing a distribution of radio waves upon the mosaic in order to produce a corresponding rectified-voltage distribution upon the rectifying elements and means for measuring the rectified voltage upon the successive rectifying elements.

References Cited in the file of this patent UNITED STATES PATENTS 1,936,514 Lengnick Nov. 21, 1933 2,288,766 \Volff July 7, 1942 2,373,396 Hefele Apr. 10, 1945 2,415,842 Oliver Feb. 18, 1947 2,423,124 Teal July 1, 1947 2,429,933 Gibson Oct. 28, 1947 2,473,893 Lyle June 21, 1949 FOREIGN PATENTS 541,959 Great Britain Dec. 19, 1941 

